| 1. |
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| 2. |
- Carney Almroth, Bethanie, 1974, et al.
(författare)
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Gender differences in health and aging of Atlantic cod subject to size selective fishery
- 2012
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Ingår i: Biology Open. - : The Company of Biologists. - 2046-6390. ; 1:9, s. 922-928
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Tidskriftsartikel (refereegranskat)abstract
- We have analyzed health and physiological aging parameters in male and female Atlantic cod, Gadus morhua, captured in Kattegat, Skagerrak and in Öresund. Gender differences were clearly evident in a number of variables. Males had longer liver telomeres and higher catalase activities than females, while females had higher superoxide dismutase activity, liver somatic index and condition factor. Effects of age were found for males where levels of the antioxidant glutathione and telomere length declined with age, indicating physiological aging. Liver somatic index increased and percentage oxidized glutathione decreased with age. Between-site comparisons of males show that percentage oxidized glutathione and catalase were lowest in Kattegat, whereas protein carbonyls and condition factor were higher in Skagerrak. Females, on the other hand, showed no differences between sites or indications of somatic aging or age-related effects in egg quality, indicating that older and larger female cod are healthy and show no changes in eggs with age. In contrast, males showed indications of physiological aging and lower condition than females. The results emphasize the importance of conserving old mature fish, in particular high egg-productive females, when managing fisheries.
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| 3. |
- Gunther, Mattias, et al.
(författare)
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Temporal gene expression changes after acute and delayed ventral root avulsion-reimplantation
- 2020
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Ingår i: Restorative Neurology and Neuroscience. - : IOS PRESS. - 0922-6028 .- 1878-3627. ; 38:1, s. 23-40
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Tidskriftsartikel (refereegranskat)abstract
- Background: In a model of injured spinal motor neurons where the avulsed spinal nerve is surgically reimplanted, useful regrowth of the injured nerve follows, both in animal experiments and clinical cases. This has led to surgical reimplantation strategies with subsequent partial functional motoric recovery. Still, the ideal time point for successful regeneration after reimplantation and the specific genetic profile of this time point is not known. Objective: To explore the temporal gene expression of the whole genome in the ventral spinal cord after reimplantation at different time points after avulsion. Methods: Totally 18 adult rats were subjected to avulsion of the left L5 root only (N = 3), avulsion followed by acute spinal reimplantation (N = 3), avulsion followed by 24 h (N = 3) or 48 h (N = 3) delayed reimplantation Animals were allowed to survive 24 h after their respective surgery whereafter the ventral quadrant of the spinal cord at the operated side was harvested, processed for and analysed with Affymetrix Rat Gene ST 1.0 array followed by statistical analysis of gene expression patterns Results: Specific gene expression patterns were found at different time points after avulsion and reimplantation. Over all, early reimplantation seemed to diminish inflammatory response and support gene regulation related to neuronal activity compared to avulsion only or delayed reimplantation. In addition did gene activity after avulsion-reimplantation correspond to regeneration-associated genes typical for regeneration in the peripheral nervous system. Conclusions: Our study reveal that genetic profiling after this kind of injury is possible, that specific and distinct expression patterns can be found with early reimplantation being favourable over late and that regenerative activity in this kind of injury bears hallmark typical for peripheral nerve regeneration. These findings can be useful in elucidating specific genetic expression typical for successful nerve regeneration, hopefully not only in this specific model but in the nervous system in general.
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| 4. |
- Nilsson Sköld, Helen, 1970, et al.
(författare)
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Stem Cells in Asexual Reproduction of Marine Invertebrates
- 2009
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Ingår i: Stem Cells in Marine Organisms. - Netherlands : Springer. - 9789048127665 ; , s. 105-137
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- While sexual reproduction is conserved and almost ubiquitous, asexual reproduction in forms of parthenogenesis or agametic cloning from somatic tissue is less conserved. The phylogeny shows that agametic cloning is widespread but scattered with many different modes for asexual formation of a new animal. This suggests that independent forms of cloning have evolved later from sexual ancestors between and within different phyla. Here, we present an overview of agametic cloning in the marine animal kingdom and discuss molecular and evolutionary aspects of somatic stem cell usage for asexual cloning. The molecular tissue characterizations and the relative role of different stem cells involved in agametic cloning are only at its beginning with whole phyla largely uncovered. An emerging hypothesis is that the first somatic stem cells used in cloning were also able to form a germ-line and that the more limited lineage specific stem cells are derived. We discuss advantages and problems with agametic cloning from somatic tissue and propose that the levels of stem cell potential held in the tissue can have large consequences for the reproductive life cycle strategies and long-term fitness in clonal animals and strains. We finally describe suitable molecular experimental approaches for future research on this topic.
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| 5. |
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Africa's changing societies : Reform from below
- 2012
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- In NAIs Annual Report 2011 you can read about how military structures lingers in Liberia, about the global rush for land, the importance of understanding local farming techniques, about how African cities drive change, and much more.
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| 6. |
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| 7. |
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| 8. |
- Andersson, Magnus, et al.
(författare)
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Fiskbestånd och miljö i hav och sötvatten : Resurs- och miljööversikt 2012
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Detta är den nionde utgåvan av den samlade översikten över fisk- och kräftdjursbeståndens status i våra vatten. Kunskap om fiskbestånden och miljön är en förutsättning för att utnyttjandet av fiskresurserna skall bli bärkraftigt. För svenska vattenområden beskrivs miljöutvecklingen i ett ekosystemsperspektiv, dels för att tydliggöra fiskens ekologiska roll och beskriva yttre miljöfaktorer som påverkar fiskbestånden, dels för att belysa fiskets effekter på miljön.Fiskbestånd och miljö i hav och sötvatten är utarbetad av Sveriges lantbruksuniversitet (SLU), Institutionen för akvatiska resurser (SLU Aqua), på uppdrag av Havs- och vattenmyndigheten. Rapporten sammanfattar utveckling och beståndsstatus för de kommersiellt viktigaste fisk- och kräftdjursarterna i våra vatten. Bedömningar och förvaltningsråd är baserade på Internationella Havsforskningsrådets (ICES) rådgivning, SLU Aquas nationella och regionala provfiskedata, samt yrkesfiskets rapportering.
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| 9. |
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| 10. |
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| 11. |
- André, Carl, 1958, et al.
(författare)
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Population structure in Atlantic cod in the eastern North Sea - Skagerrak - Kattegat: early life stage dispersal and adult migration
- 2016
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Ingår i: BMC Research Notes. - : Springer Science and Business Media LLC. - 1756-0500. ; 9:63
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Tidskriftsartikel (refereegranskat)abstract
- Background: In marine fish species, where pelagic egg and larvae drift with ocean currents, population structure has been suggested to be maintained by larval retention due to hydrographic structuring and by homing of adult fish to natal areas. Whilst natal homing of adults has been demonstrated for anadromous and coral reef fishes, there are few documented examples of philopatric migration in temperate marine fish species. Results: Here, we demonstrate temporally stable genetic differentiation among spawning populations of Atlantic cod (Gadus morhua L.), and present genetic and behavioural evidence for larval drift and philopatric migration in the eastern North Sea-Skagerrak-Kattegat area. We show that juvenile cod collected in the eastern Skagerrak and central Kattegat are genetically similar to cod from offshore spawning areas in the eastern North Sea. Genetic assignment of individual 2-5 year old fish indicates that cod residing at, or migrating towards, spawning areas in Kattegat and the North Sea display philopatric behaviours. Conclusions: Together these findings suggest a loop between spawning, larval drift and adult return-migrations to spawning areas and underlines that both oceanographic processes and migratory behaviour in the adult phase may be important for stock separation and integrity in marine temperate fishes such as Atlantic cod. © 2016 André et al.
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| 12. |
- Belgrano, Andrea, et al.
(författare)
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Mapping and Evaluating Marine Protected Areas and Ecosystem Services: A Transdisciplinary Delphi Forecasting Process Framework
- 2021
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Marine Protected Areas (MPAs) are an important tool for management and conservation and play an increasingly recognised role in societal and human well-being. However, the assessment of MPAs often lacks a simultaneous consideration of ecological and socio-economic outcomes, and this can lead to misconceptions on the effectiveness of MPAs. In this perspective, we present a transdisciplinary approach based on the Delphi method for mapping and evaluating Marine Protected Areas for their ability to protect biodiversity while providing Ecosystem Services (ES) and related human well-being benefits – i.e., the ecosystem outputs from which people benefit. We highlight the need to include the human dimensions of marine protection in such assessments, given that the effectiveness of MPAs over time is conditional on the social, cultural and institutional contexts in which MPAs evolve. Our approach supports Ecosystem-Based Management and highlights the importance of MPAs in achieving restoration, conservation, and sustainable development objectives in relation to EU Directives such as the Marine Strategy Framework Directive (MSFD), the Maritime Spatial Planning Directive (MSPD), and the Common Fisheries Policy (CFP).
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| 13. |
- Bergen, K., et al.
(författare)
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Neurite Growth and Polarization on Vitronectin Substrate after in Vitro Trauma is not Enhanced after IGF Treatment
- 2018
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Ingår i: Brain Sciences. - : MDPI. - 2076-3425. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- Following traumatic brain injuries (TBI), insulin-like growth factor (IGF) is cortically widely upregulated. This upregulation has a potential role in the recovery of neuronal tissue, plasticity, and neurotrophic activity, though the molecular mechanisms involved in IGF regulation and the exact role of IGF after TBI remain unclear. Vitronectin (VN), an extracellular matrix (ECM) molecule, has recently been shown to be of importance for IGF-mediated cellular growth and migration. Since VN is downregulated after TBI, we hypothesized that insufficient VN levels after TBI impairs the potential beneficial activity of IGF. To test if vitronectin and IGF-1/IGFBP-2 could contribute to neurite growth, we cultured hippocampal neurons on +/- vitronectin-coated coverslips and them treated with +/- IGF-1/IGF binding protein 2 (IGFBP-2). Under same conditions, cell cultures were also subjected to in vitro trauma to investigate differences in the posttraumatic regenerative capacity with +/- vitronectin-coated coverslips and with +/- IGF-1/IGFBP-2 treatment. In both the control and trauma situations, hippocampal neurons showed a stronger growth pattern on vitronectin than on the control substrate. Surprisingly, the addition of IGF-1/IGFBP-2 showed a decrease in neurite growth. Since neurite growth was measured as the number of neurites per area, we hypothesized that IGF-1/IGFBP-2 contributes to the polarization of neurons and thus induced a less dense neurite network after IGF-1/IGFBP-2 treatment. This hypothesis could not be confirmed and we therefore conclude that vitronectin has a positive effect on neurite growth in vitro both under normal conditions and after trauma, but that addition of IGF-1/IGFBP-2 does not have a positive additive effect.
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| 14. |
- Bergström, Ulf, et al.
(författare)
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Ekologiska effekter av fiskefria områden i Sveriges kust- och havsområden
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna rapport beskriver de ekologiska effekterna av fiskefria områden i svenska kust- och havsområden. År 2005 fick dåvarande Fiskeriverket, numera Havs- och vattenmyndigheten, i uppdrag att införa och utvärdera effekterna av fiskefria områden. Fem fiskefria områden bildades 2009-2011 och utvecklingen av fiskbestånd, i vissa fall även andra delar av ekosystemen, har följts till och med 2015. Rapporten fokuserar på de delar av regeringsuppdraget som syftar till att utvärdera de biologiska effekterna av fiskefria områden samt att bedöma fiskets påverkan på fiskbestånd och ekosystem. När områdena inrättats 2011 utgjorde de svenska fiskefria områdena, inklusive de som fanns sedan tidigare, nästan 1200 km2. Detta motsvarar mindre än 1 % av de svenska havsområdena, men samtidigt två tredjedelar av den totala ytan fiskefria områden i hela Europa. Detta innebär att det svenska arbetet med utvärderingar av fiskefria områden är av stort intresse även internationellt sett. De områden och målarter som ingått i utvärderingen är: · Sik i Bottenhavet · Gös, gädda och abborre i Stockholms skärgård · Torsk i Kattegatt · Hummer och rovfisk i Göteborgs skärgård · Torsk, piggvar och rödspotta i fjordsystemet innanför Orust och Tjörn Effekterna av dessa fiskefria områden beskrivs detaljerat i varsin delrapport. Generellt har en tydlig återhämtning hos målarterna skett. Antalet individer och storleken på fisken har ökat i de fiskefria områdena i förhållande till referensområden där fiske fortsatt varit tillåtet. Resultaten visar att fisket på de aktuella bestånden tidigare varit av sådan omfattning att det påverkat både beståndsstorlek och storleksstruktur. De positiva effekterna ses både för bestånd där yrkesfisket stått för merparten av fångsterna, exempelvis torsk i Kattegatt, och för kustarter där fritidsfisket dominerat fångsterna, som till exempel sik i Bottenhavet, gös i Stockholms skärgård och hummer i Göteborgs skärgård. Trots den korta utvärderingsperioden på ca 5 år har alltså bestånden svarat med tydliga ökningar, vilket visar att fiskefria områden är en effektiv åtgärd för att snabbt stärka försvagade bestånd. I ett av de undersökta områdena, Havstensfjorden, har däremot inga positiva effekter kunnat påvisas hittills. Sannolikt har de lokala bestånden av främst torsk och rödspotta i detta område befunnit sig på en så låg nivå före fredningen att de varit rekryteringsöverfiskade. Det kan därmed ta lång tid för dessa bestånd att återhämta sig. Även effekter på fisksamhällena som helhet och på bottenfauna har kunnat konstateras i de fiskefria områden där dessa delar av ekosystemet undersökts. Troligen beror förändringarna på en kombination av direkta effekter på målarterna och bifångstarter genom att fisket upphört, samt på indirekta effekter genom en ökad predation från stor rovfisk och hummer på bytesarter. Genom att mängden rovfiskar ökar bidrar fiskefria områden till att återställa ekosystemfunktioner, och kan exempelvis motverka massförekomster av snabbväxande alger, och de problem dessa förorsakar, genom så kallade trofiska kaskader. Ytterligare en effekt av fiskeförbud är att den fysiska störningen av bottendjurssamhällen från bottentrålning minskar och att arter som är känsliga för fysisk påverkan därmed gynnas. I de flesta fall har införandet av de fiskefria områdena sannolikt lett till ett minskat fiske snarare än en förflyttning av fisket till angränsande områden. I Kattegatt var syftet med det fiskefria området och buffertzonerna att flytta det oselektiva blandfisket med bottentrål efter havskräfta och plattfisk till områden där risken att fånga vuxen lekmogen torsk var lägre. Blandfiskena efter havskräfta och plattfisk har kunnat ta upp sina kvoter och kunnat fortgå i buffertområdena efter lekperioden och utanför det fiskefria området, men nu med minskade oavsiktliga fångster av vuxen torsk. I rapporten sammanfattas även det internationella kunskapsläget angående fiskefria områden, liksom resultaten från fyra tidigare studerade svenska fiskefria områden. Effekterna i de tidigare undersökta svenska områdena överensstämmer i stort med de som påvisats i de nu aktuella studierna, med positiva effekter på beståndstäthet och storleksstruktur samt en påföljande ökning i reproduktionspotential. Resultaten är även i linje med internationella studier när det gäller effekter på fiskbestånd. För de svenska fiskefria områdena råder däremot brist på direkta studier av ekosystemeffekter av stängningarna. Det finns emellertid kunskap från andra forskningsprojekt i svenska vatten som visar på kopplingen mellan rovfiskbestånd och ekosystemens funktion, framför allt genom trofiska kaskader. Nettoeffekterna av fiskefria områden för fisket är ofta svåra att bedöma. I och med att fiskarna blir fler och större inom de fiskefria områdena ökar även reproduktionen, vilket kan ge positiva effekter på bestånden utanför de stängda områdena genom export av ägg och larver och migration av äldre fisk. Storleken på sådana spilleffekter är dock svår att mäta. Även om exporten av fisk från fiskefria områden inte alltid kan uppväga förlusten av fiskeområden för fisket, så kan de bidra med andra positiva effekter. Genom att en del av fiskbestånden undantas från fiske minskas risken för beståndskollaps till följd av i övrigt otillräckliga åtgärder inom fiskförvaltningen, och de fiskefria områdena fungerar därmed som en försäkring. Samtidigt kan fiskefria områden motverka den genetiska utarmning som kan ske genom ett selektivt fiske på snabbväxande och storvuxna individer, vilket på sikt annars kan leda till en minskad fiskresurs, liksom en lägre biologisk variation och resiliens mot andra förändringar i miljön. I Kattegatt har nettoeffekten av åtgärderna kunnat mätas. Effekten är positiv på beståndet som helhet, eftersom torsken visar tecken på återhämtning i hela havsområdet. Det fiskefria området har inte begränsat fångstuttaget av andra kvoterade arter än torsk. På sikt ger återhämtningen förutsättningar för ett ökat fiske av torsk, eftersom beståndet sprider sig utanför det fiskefria området efter lekperioden. Fiskefria områden kan om de är väl utformade ge positiva beståndseffekter och därmed komplettera andra regleringar inom fiskförvaltningen. I många fall kan goda resultat uppnås med mindre drastiska åtgärder, exempelvis genom redskaps- eller fångstbegränsningar i tid och rum. Denna utvärdering visar att fiskefria områden kan vara viktiga för förvaltning i synnerhet av blandfisken och fisken på lokala kustbestånd, samt för att motverka negativa effekter på ekosystemet av fiske. Marina skyddade områden där skydd av både fisk och deras livsmiljöer kombineras, är därför ett viktigt instrument för en ekosystembaserad förvaltning. Inom havsmiljöarbetet behövs fiskefria områden också som referensområden för att kunna sätta mål för den ekologiska statusen i kust- och havsmiljö och för att bättre förstå fiskets effekter på bestånd och ekosystem i relation till andra påverkansfaktorer.
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| 15. |
- Bergström, Ulf, et al.
(författare)
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Inför fler fiskefria områden för att skydda bestånd och ekosystem
- 2024
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fiskefria områden kan vara ett effektivt verktyg för att skydda både fisk- och kräftdjursbestånd och marina ekosystem. Men det är viktigt att områdena utformas på rätt sätt och är tillräckligt stora. Lektidsfredade områden kan vara enklare att driva igenom, men ger inte lika goda effekter.
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| 16. |
- Bergström, Ulf, et al.
(författare)
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Long-term effects of no-take zones in Swedish waters
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Marine protected areas (MPAs) are increasingly established worldwide to protect and restore degraded ecosystems. However, the level of protection varies among MPAs and has been found to affect the outcome of the closure. In no-take zones (NTZs), no fishing or extraction of marine organisms is allowed. The EU Commission recently committed to protect 30% of European waters by 2030 through the updated Biodiversity Strategy. Importantly, one third of these 30% should be of strict protection. Exactly what is meant by strict protection is not entirely clear, but fishing would likely have to be fully or largely prohibited in these areas. This new target for strictly protected areas highlights the need to evaluate the ecological effects of NTZs, particularly in regions like northern Europe where such evaluations are scarce. The Swedish NTZs made up approximately two thirds of the total areal extent of NTZs in Europe a decade ago. Given that these areas have been closed for at least 10 years and can provide insights into long-term effects of NTZs on fish and ecosystems, they are of broad interest in light of the new 10% strict protection by 2030 commitment by EU member states.In total, eight NTZs in Swedish coastal and offshore waters were evaluated in the current report, with respect to primarily the responses of focal species for the conservation measure, but in some of the areas also ecosystem responses. Five of the NTZs were established in 2009-2011, as part of a government commission, while the other three had been established earlier. The results of the evaluations are presented in a synthesis and also in separate, more detailed chapters for each of the eight NTZs. Overall, the results suggest that NTZs can increase abundances and biomasses of fish and decapod crustaceans, given that the closed areas are strategically placed and of an appropriate size in relation to the life cycle of the focal species. A meta-regression of the effects on focal species of the NTZs showed that CPUE was on average 2.6 times higher after three years of protection, and 3.8 times higher than in the fished reference areas after six years of protection. The proportion of old and large individuals increased in most NTZs, and thereby also the reproductive potential of populations. The increase in abundance of large predatory fish also likely contributed to restoring ecosystem functions, such as top-down control. These effects appeared after a 5-year period and in many cases remained and continued to increase in the longer term (>10 years). In the two areas where cod was the focal species of the NTZs, positive responses were weak, likely as an effect of long-term past, and in the Kattegat still present, recruitment overfishing. In the Baltic Sea, predation by grey seal and cormorant was in some cases so high that it likely counteracted the positive effects of removing fisheries and led to stock declines in the NTZs. In most cases, the introduction of the NTZs has likely decreased the total fishing effort rather than displacing it to adjacent areas. In the Kattegat NTZ, however, the purpose was explicitly to displace an unselective coastal mixed bottom-trawl fishery targeting Norway lobster and flatfish to areas where the bycatches of mature cod were smaller. In two areas that were reopened to fishing after 5 years, the positive effects of the NTZs on fish stocks eroded quickly to pre-closure levels despite that the areas remained closed during the spawning period, highlighting that permanent closures may be necessary to maintain positive effects.We conclude from the Swedish case studies that NTZs may well function as a complement to other fisheries management measures, such as catch, effort and gear regulations. The experiences from the current evaluation show that NTZs can be an important tool for fisheries management especially for local coastal fish populations and areas with mixed fisheries, as well as in cases where there is a need to counteract adverse ecosystem effects of fishing. NTZs are also needed as reference for marine environmental management, and for understanding the effects of fishing on fish populations and other ecosystem components in relation to other pressures. MPAs where the protection of both fish and their habitats is combined may be an important instrument for ecosystembased management, where the recovery of large predatory fish may lead to a restoration of important ecosystem functions and contribute to improving decayed habitats.With the new Biodiversity Strategy, EUs level of ambition for marine conservation increases significantly, with the goal of 30% of coastal and marine waters protected by 2030, and, importantly, one third of these areas being strictly protected. From a conservation perspective, rare, sensitive and/or charismatic species or habitats are often in focus when designating MPAs, and displacement of fisheries is then considered an unwanted side effect. However, if the establishment of strictly protected areas also aims to rebuild fish stocks, these MPAs should be placed in heavily fished areas and designed to protect depleted populations by accounting for their home ranges to generate positive outcomes. Thus, extensive displacement of fisheries is required to reach benefits for depleted populations, and need to be accounted for e.g. by specific regulations outside the strictly protected areas. These new extensive EU goals for MPA establishment pose a challenge for management, but at the same time offer an opportunity to bridge the current gap between conservation and fisheries management.
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| 17. |
- Borg, Mattias, et al.
(författare)
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Characterization of GaSb nanowires grown by MOVPE
- 2008
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Ingår i: Journal of Chrystal Growth. - : Elsevier BV. - 0022-0248. ; 310:23, s. 5119-5122
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Konferensbidrag (refereegranskat)abstract
- We report the growth and characterization of GaSb nanowires grown by MOVPE. The structural properties of the nanowires are investigated by the means of transmission electron microscopy, X-ray diffraction and single nanowire photoluminescence. The measurements confirm a high material quality in the GaSb nanowires. Also, a back-gated nanowire transistor structure is used to extract values for the polarity and resistivity of the GaSb. Finally, a simple kinetic model is presented to explain the non-linear time dependence of the GaSb nanowire growth. (C) 2008 Elsevier B.V. All rights reserved.
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| 18. |
- Bradshaw, Clare, et al.
(författare)
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Bottom trawling resuspends sediment and releases bioavailable contaminants in a polluted fjord
- 2012
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 170, s. 232-241
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Tidskriftsartikel (refereegranskat)abstract
- Sediments are sinks for contaminants in the world's oceans. At the same time, commercial bottom trawling is estimated to affect around 15 million km(2) of the world's seafloor every year. However, few studies have investigated whether this disturbance remobilises sediment-associated contaminants and, if so, whether these are bioavailable to aquatic organisms. This field study in a trawled contaminated Norwegian fjord showed that a single 1.8 km long trawl pass created a 3-5 million m(3) sediment plume containing around 9 t contaminated sediment; ie. 200 g dw m(-2) trawled, equivalent to c. 10% of the annual gross sedimentation rate. Substantial amounts of PCDD/Fs and non-ortho PCBs were released from the sediments, likely causing a semi-permanent contaminated sediment suspension in the bottom waters. PCDD/Fs from the sediments were also taken up by mussels which, during one month, accumulated them to levels above the EU maximum advised concentration for human consumption.
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| 19. |
- Bradshaw, Clare, 1972-, et al.
(författare)
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Effects of bottom trawling and environmental factors on benthic bacteria, meiofauna and macrofauna communities and benthic ecosystem processes
- 2024
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Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 921
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Tidskriftsartikel (refereegranskat)abstract
- Soft sediment marine benthic ecosystems comprise a diverse community of bacteria, meiofauna and macrofauna, which together support a range of ecosystem processes such as biogeochemical cycling. These ecosystems are also fishing grounds for demersal species that are often caught using bottom trawling. This fishing method can have deleterious effects on benthic communities by causing injury or mortality, and through alteration of sediment properties that in turn influence community structure. Although the impacts of bottom trawling on macrofauna are relatively well studied, less is known about the responses of meiofauna and bacteria to such disturbances, or how bottom trawling impacts benthic ecosystem processes. Quantifying trawling impacts against a background of natural environmental variability is also a challenge. To address these questions, we examined effects of bottom trawling and a range of environmental variables (e. g. water chemistry and physical and biochemical surface sediment properties) on a) bacterial, meiofaunal and macrofaunal community structure and b) benthic ecosystem processes (nutrient fluxes, extracellular enzyme activities and carbon turnover and degradation rates). We also investigated the link between the benthic macrofauna community and the same ecosystem processes. While there was a significant effect of bottom trawling intensity on macrofaunal community structure, the same was not seen for bacterial or meiofaunal community composition, which were more affected by environmental factors, such as surface sediment properties. The labile component of the surface sediment carbon pool was higher at highly trawled sites. Carbon degradation rates, extracellular enzyme activities, oxygen fluxes and some nutrient fluxes were significantly affected by trawling, but ecosystem processes were also strongly linked to the abundance of key bioturbators (Macoma balthica, Halicryptus spinulosus, Scoloplos armiger and Pontoporeia femorata). Although benthic ecosystems were affected by a combination of trawling and natural variability, disentangling these showed that the anthropogenic effects were clearest on the larger component of the community, i.e. macrofauna composition, and on ecosystem processes related to sedimentary carbon.
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| 20. |
- Bradshaw, Clare, et al.
(författare)
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Physical Disturbance by Bottom Trawling Suspends Particulate Matter and Alters Biogeochemical Processes on and Near the Seafloor
- 2021
-
Ingår i: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 8
-
Tidskriftsartikel (refereegranskat)abstract
- Bottom trawling is known to affect benthic faunal communities but its effects on sediment suspension and seabed biogeochemistry are less well described. In addition, few studies have been carried out in the Baltic Sea, despite decades of trawling in this unique brackish environment and the frequent occurrence of trawling in areas where hypoxia and low and variable salinity already act as ecosystem stressors. We measured the physical and biogeochemical impacts of an otter trawl on a muddy Baltic seabed. Multibeam bathymetry revealed a 36 m-wide trawl track, comprising parallel furrows and sediment piles caused by the trawl doors and shallower grooves from the groundgear, that displaced 1,000 m3 (500 t) sediment and suspended 9.5 t sediment per km of track. The trawl doors had less effect than the rest of the gear in terms of total sediment mass but per m2 the doors had 5× the displacement and 2× the suspension effect, due to their greater penetration and hydrodynamic drag. The suspended sediment spread >1 km away over the following 3–4 days, creating a 5–10 m thick layer of turbid bottom water. Turbidity reached 4.3 NTU (7 mgDW L–1), 550 m from the track, 20 h post-trawling. Particulate Al, Ti, Fe, P, and Mn were correlated with the spatio-temporal pattern of suspension. There was a pulse of dissolved N, P, and Mn to a height of 10 m above the seabed within a few hundred meters of the track, 2 h post-trawling. Dissolved methane concentrations were elevated in the water for at least 20 h. Sediment biogeochemistry in the door track was still perturbed after 48 h, with a decreased oxygen penetration depth and nutrient and oxygen fluxes across the sediment-water interface. These results clearly show the physical effects of bottom trawling, both on seabed topography (on the scale of km and years) and on sediment and particle suspension (on the scale of km and days-weeks). Alterations to biogeochemical processes suggest that, where bottom trawling is frequent, sediment biogeochemistry may not have time to recover between disturbance events and elevated turbidity may persist, even outside the trawled area.
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| 21. |
- Bryhn, Andreas, et al.
(författare)
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Kunskapsunderlag om möjliga icke-torskfiskerelaterade åtgärder för att torskbestånd ska bevaras och återhämta sig i svenska vatten
- 2020
-
Rapport (refereegranskat)abstract
- Torsk (Gadus morhua) är en viktig art för marina ekosystem i Sverige, där den har en strukturerande och reglerande funktion i relation till andra arter. Torsken har under historiens gång även spelat en viktig roll för samhället i Sverige inom dess nuvarande gränsers område (Bohuslän har t.ex. inte alltid tillhört Sverige), som en målart för fiske. Samtliga torskbestånd som återfinns i havsområdena runt Sverige har nu dålig status och det internationella havsforskningsrådet ICES rekommenderar låg eller ingen fångst, beroende på bestånd. Utöver riktat fiske påverkas dock torsken av en rad andra faktorer som exempelvis bifångster i annat fiske, syrebrist, klimatförändringar, predatorer, parasiter, bottenpåverkan av trålning, förlust av uppväxtmiljöer, födobrist, tiaminbrist och giftiga ämnen. Denna rapport diskuterar möjligheter att skydda och bevara torsken på sätt som kan komplettera begränsningar i det riktade torskfisket. Torskens situation är komplex och rapporten är därför skriven utifrån ett ekosystemperspektiv för att möjliggöra en bredare ansats i förvaltningen av torskbestånd i svenska vatten, där alla relevanta påverkansfaktorer bör beaktas. Det bör poängteras att denna rapport inte har gjort någon ny utredning av påverkansfaktorernas effekter, utan har istället gjort en litteratursammanställning och en kvalitativ analys. Vi har ändå valt att lyfta fram vissa åtgärder som särskilt potentiellt betydelsefulla - en samlad kvalitativ expertbedömning som rangordnar olika åtgärders effektivitet för återuppbyggnad per bestånd, se avsnitt 6 i rapporten.
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| 22. |
- Bryhn, Andreas, et al.
(författare)
-
Which factors can affect the productivity and dynamics of cod stocks in the Baltic Sea, Kattegat and Skagerrak?
- 2022
-
Ingår i: Ocean and Coastal Management. - : Elsevier BV. - 0964-5691 .- 1873-524X. ; 223
-
Forskningsöversikt (refereegranskat)abstract
- Stocks of Atlantic cod (Gadus morhua) in the Baltic Sea, Kattegat and Skagerrak (N. Europe) have been strongly exploited for decades bringing them into an enduringly depleted status. Scientific cod stock related advice for targeted and mixed fisheries is provided on an annual basis by the International Council for Exploration of the Sea. This advice forms a basis for ministerial decisions on, e.g., the total allowable catch and management plans. Despite measures to reduce fishing-induced mortality of cod, such as catch and effort restrictions, increased gear selectivity, closed areas and seasons, clear signs of recovery are yet to be seen. Thus, traditional advice for the management of these stocks may have to be complemented by advice on supporting measures focusing on other pressures hampering the recovery of cod. The present study elaborates on potential supportive measures for cod stock recovery in the Baltic Sea, Kattegat, and Skagerrak (including local populations where applicable), based on current knowledge. The list of measures presented here is the outcome of in-depth discussions on the state-of-the-art knowledge, among cod experts and further with stakeholders with the aim to follow principles of ecosystem-based fisheries management. Following the identification of different pressures on and prerequisites for the separate stocks, the listed measures differ between stocks and include cod bycatch mortality reduction, alterations in fisheries affecting food sources for cod, restocking, protection of juvenile habitats, and reduced predation. The literature review and the list of measures are intended to provide decision-support for managers and policymakers aiming to provide conditions for the cod stocks to recover.
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| 23. |
- Cao, Yuli, et al.
(författare)
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Cellular High-Energy Cavitation Trauma - Description of a Novel In Vitro Trauma Model in Three Different Cell Types
- 2016
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Ingår i: Frontiers in Neurology. - : Frontiers Media SA. - 1664-2295. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- The mechanisms involved in traumatic brain injury have yet to be fully characterized. One mechanism that, especially in high-energy trauma, could be of importance is cavitation. Cavitation can be described as a process of vaporization, bubble generation, and bubble implosion as a result of a decrease and subsequent increase in pressure. Cavitation as an injury mechanism is difficult to visualize and model due to its short duration and limited spatial distribution. One strategy to analyze the cellular response of cavitation is to employ suitable in vitro models. The flyer-plate model is an in vitro high-energy trauma model that includes cavitation as a trauma mechanism. A copper fragment is accelerated by means of a laser, hits the bottom of a cell culture well causing cavitation, and shock waves inside the well and cell medium. We have found the flyer-plate model to be efficient, reproducible, and easy to control. In this study, we have used the model to analyze the cellular response to microcavitation in SH-SY5Y neuroblastoma, Caco-2, and C6 glioma cell lines. Mitotic activity in neuroblastoma and glioma was investigated with BrdU staining, and cell numbers were calculated using automated time-lapse imaging. We found variations between cell types and between different zones surrounding the lesion with these methods. It was also shown that the injured cell cultures released S-100B in a dose-dependent manner. Using gene expression microarray, a number of gene families of potential interest were found to be strongly, but differently regulated in neuroblastoma and glioma at 24 h post trauma. The data from the gene expression arrays may be used to identify new candidates for biomarkers in cavitation trauma. We conclude that our model is useful for studies of trauma in vitro and that it could be applied in future treatment studies.
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| 24. |
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| 25. |
- Cardinale, Massimiliano, et al.
(författare)
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Variability and connectivity of plaice populations from the Eastern North Sea to the Western Baltic Sea, and implications for assessment and management
- 2013
-
Ingår i: Journal of Sea Research. - : Elsevier BV. - 1385-1101 .- 1873-1414. ; 84, s. 40-48
-
Tidskriftsartikel (refereegranskat)abstract
- An essential prerequisite of sustainable fisheries is the match between biologically relevant processes and management action. Various populations may however co-occur on fishing grounds, although they might not belong to the same stock, leading to poor performance of stock assessment and management. Plaice in Kattegat and Skagerrak have traditionally been considered as one stock unit. Current understanding indicates that several plaice components may exist in the transition area between the North Sea and the Baltic Sea. A comprehensive review of all available biological knowledge on plaice in this area is performed, including published and unpublished literature together with the analyses of commercial and survey data and historical tagging data. The results suggest that plaice in Skagerrak is closely associated with plaice in the North Sea, although local populations are present in the area Plaice in Kattegat, the Belts Sea and the Sound can be considered a stock unit, as is plaice in the Baltic Sea. The analyses revealed great heterogeneity in the dynamics and productivity of the various local components, and suggested for specific action to maintain biodiversity. (C) 2013 Elsevier B.V. All rights reserved.
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| 26. |
- Corell, Hanna, et al.
(författare)
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Sediment suspended by bottom trawling can reduce reproductive success in a broadcast spawning fish
- 2023
-
Ingår i: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714 .- 1096-0015. ; 282
-
Tidskriftsartikel (refereegranskat)abstract
- Suspended sediment adheres to pelagic fish eggs, affecting their buoyancy. In the stratified southern Baltic Sea, eggs of the Eastern cod depend on neutral buoyancy in the “reproductive volume” (RV) (approx. >11 salinity and >2 ml O2/L) for successful hatching. With increased suspended sediment concentrations (SSC), eggs risk sinking out of the RV into deeper, unfavourable conditions. Bottom trawling, which increases SSC, has been intense around the Eastern cod spawning ground. We modelled the transport of sediment suspended from trawling at this spawning ground to estimate the degree to which eggs could be affected by increased SSC. SSC >1 mg/L above background levels was found 3 km away, one trawl track subjecting a water volume equivalent to 0.01% of the RV to this excess SSC for >12 h. At this excess SSC, it would take c. 6 d for an egg to sink out into unfavourable conditions; insufficient time for it to become a larva. Extrapolating to real bottom trawling intensities in the area of the RV where suspension is highest showed that a water volume equivalent to half the RV experiences excess turbidity of >1 mg/L for c. 24 h during a year. However, fishing effort is heterogeneous; spatio-temporal overlap between trawling and the RV will enhance the duration and/or frequency of turbidity in the spawning area, affecting a higher fraction of the eggs than the model predicts. We conclude that bottom trawling at this spawning ground could decrease cod's reproductive success through increased SSC. Such effects are likely in populations of other fish with pelagic eggs that spawn at trawling grounds.
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| 27. |
- Elmi Terander, Adrian, et al.
(författare)
-
Spinal neurokirurgi på grund av radikulopati och myelopat : [Spinal neurosurgery radiculopathy and myelopathy]
- 2023
-
Ingår i: Läkartidningen. - : Läkartidningen Förlag. - 0023-7205 .- 1652-7518. ; 120
-
Tidskriftsartikel (refereegranskat)abstract
- The field of spinal neurosurgery covers degenerative conditions and trauma as well as tumors, malformations and vascular disorders of spine and spinal cord. This article focuses on the Swedish spinal neurosurgical care regarding radiculopathy and myelopathy. Disc herniation, foraminal stenosis, spinal stenosis and spinal cord compression due to degenerative disorders or tumors are discussed. Treatment options such as anterior cervical decompression and fusion, posterior forami-notomy, laminectomy and approaches to spinal intradural tumors are briefly presented. The aim is to present symptoms, diagnostics and treatment options of common conditions to facilitate early detection and referral to neurosurgical centers to avoid delayed dia-gnosis and neurological impairment.
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| 28. |
- Emanuelsson, Andreas, et al.
(författare)
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Accounting for overfishing in life cycle assessment: new impact categories for biotic resource use
- 2014
-
Ingår i: International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 0948-3349 .- 1614-7502. ; 19:5, s. 1156-1168
-
Tidskriftsartikel (refereegranskat)abstract
- Overfishing is a relevant issue to include in all life cycle assessments (LCAs) involving wild caught fish, as overfishing of fish stocks clearly targets the LCA safeguard objects of natural resources and natural ecosystems. Yet no robust method for assessing overfishing has been available. We propose lost potential yield (LPY) as a midpoint impact category to quantify overfishing, comparing the outcome of current with target fisheries management. This category primarily reflects the impact on biotic resource availability, but also serves as a proxy for ecosystem impacts within each stock. LPY represents average lost catches owing to ongoing overfishing, assessed by simplified biomass projections covering different fishing mortality scenarios. It is based on the maximum sustainable yield concept and complemented by two alternative methods, overfishing though fishing mortality (OF) and overfishedness of biomass (OB), that are less data-demanding. Characterization factors are provided for 31 European commercial fish stocks in 2010, representing 74 % of European and 7 % of global landings. However, large spatial and temporal variations were observed, requiring novel approaches for the LCA practitioner. The methodology is considered compliant with the International Reference Life Cycle Data System (ILCD) standard in most relevant aspects, although harmonization through normalization and endpoint characterization is only briefly discussed. Seafood LCAs including any of the three approaches can be a powerful communicative tool for the food industry, seafood certification programmes, and for fisheries management.
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| 29. |
- Englund, Eva, et al.
(författare)
-
Tactical Radio Access Networks based on Future Civilian Communication Architectures
- 1999
-
Konferensbidrag (refereegranskat)abstract
- We investigate architectures where a tactical radio subsystem can integrate in civilian systems. The idea is that civilian communication infrastructure sould be used whereever it is available. One such possibility may be found in the proposed next generation wireless communication system UMTS, where the defition of a Radio Network Subsystem (RNS), encapsulating all the features of wireless mobile communications has been proposed. We adopt this design paradigm to see if it is possible to find a low cost military network (by maximal use of civilian network technology and communication applications). The idea is to within the framework of an RNS, encapsulate also features specific to tactical wireless communications, a Tactical Radio Access Network (TRAN). Based on UMTS we describe two system concepts and architectures for designing a TRAN. Furthermore, feasibility investigation of the concepts is conducted.
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| 30. |
-
Fisk, fiske och miljö : Fiskeriverkets miljömålsarbete 2001-2004
- 2004
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I sitt regleringsbrev för år 2004 fick Fiskeriverket i uppdrag att lämna en särskild delrapport över de för år 2003 specificerade uppdragen för miljökvalitetsmålen Hav i balans samt levande kust och skärgård, Levande sjöar och vattendrag och Storslagen fjällmiljö. Fiskeriverketsredovisning omfattar inte bara de särskilt specificerade uppdragen utan också Fiskeriverkets övriga arbete för att uppnå miljökvalitetsmålen. Miljömålsarbetet under första halvan år 2004 ingår också i rapporten.Fiskeriverket fick 1998 ett särskilt sektorsansvar för ekologiskt hållbar utveckling och skall, som ett led i detta, verka för en god fiskevård och främja den biologiska mångfalden och därmed ett rikt och varierat fiskbestånd. Målsättningarna för sektorsansvaret formulerades i rapporten Fiskeriverkets sektorsmål för ekologiskt hållbar utveckling (Fiskeriverket informerar 1999:7). Rapporten utgjorde underlag till de svenska miljökvalitetsmålen "Hav i balans samt levande kust och skärgård" och "Levande sjöar och vattendrag".För Fiskeriverket innebär arbetet med miljökvalitetsmålen att målen så långt möjligt integreras i Fiskeriverkets arbete i sin helhet. Dessutom arbetar Fiskeriverket målinriktat med forskning och utveckling för att ta fram ny kunskap som ska ligga till grund för åtgärder som bidrar till att uppnå de delmål där Fiskeriverket har ett ansvar.
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| 31. |
- Glaas, Erik, 1981-, et al.
(författare)
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Managing climate change vulnerabilities: formal institutions and knowledge use as determinants of adaptive capacity at the local level in Sweden
- 2010
-
Ingår i: Local Environment. - London : Routledge. - 1354-9839 .- 1469-6711. ; 15:6, s. 525-539
-
Tidskriftsartikel (refereegranskat)abstract
- Though managing vulnerabilities posed by climate change calls for effective strategies and measures, its challenges have hitherto not been fully understood. In Sweden, municipalities have recently started incorporating vulnerability management into their political and administrative agendas. This study discusses such experiences and explores how institutional determinants may influence adaptive capacity within a local case study area, to illustrate emerging challenges and opportunities for Swedish municipalities in managing climate vulnerabilities. Specifically, formal institutional structure and the use of knowledge are analysed, concluding that vulnerability management often is focused on technical and reactive fixes, due to limited cooperation between local sector organisations, lack of local co-ordination, and an absence of methods and traditions to build institutional knowledge. Even so, opportunities, such as a high capacity to examine risks to technical systems and important establishments which in turn facilitates protection of technical infrastructure exposed to climate variability and change, also exist.
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| 32. |
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| 33. |
- Gonzalez-Mirelis, Genoveva, 1977, et al.
(författare)
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Using Vessel Monitoring System Data to Improve Systematic Conservation Planning of a Multiple-Use Marine Protected Area, the Kosterhavet National Park (Sweden)
- 2014
-
Ingår i: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 43:2, s. 162-174
-
Tidskriftsartikel (refereegranskat)abstract
- When spatial fishing data is fed into systematic conservation planning processes the cost to a fishery could be ensured to be minimal in the zoning of marine protected areas. We used vessel monitoring system (VMS) data to map the distribution of prawn trawling and calculate fish- ing intensity for 1-ha grid cells, in the Kosterhavet National Park (Sweden). We then used the software Marxan to generate cost-efficient reserve networks that represented every biotope in the Park. We asked what were the potential gains and losses in terms of fishing effort and species conservation of different planning scenarios. Given a conservation target of 10 % representation of each bio- tope, the fishery need not lose more than 20 % of its fishing grounds to give way to cost-efficient conservation of ben- thic diversity. No additional reserved area was needed to achieve conservation targets while minimizing fishing costs. We discuss the benefits of using VMS data for conservation planning.
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| 34. |
- Hansen, Kjetil Falkenberg, Docent, 1972-, et al.
(författare)
-
Student involvement in sound and music computing research : Current practices at KTH and KMH
- 2019
-
Ingår i: Combined proceedings of the Nordic Sound and Music Computing Conference 2019 and the Interactive Sonification Workshop 2019. - Stockholm. ; , s. 36-42
-
Konferensbidrag (refereegranskat)abstract
- To engage students in and beyond course activities has been a working practice both at KTH Sound and Music Computing group and at KMH Royal College of Music since many years. This paper collects experiences of involving students in research conducted within the two institutions. We describe how students attending our courses are given the possibility to be involved in our research activities, and we argue that their involvement both contributes to develop new research and benefits the students in the short and long term. Among the assignments, activities, and tasks we offer in our education programs are pilot experiments, prototype development, public exhibitions, performing, composing, data collection, analysis challenges, and bachelor and master thesis projects that lead to academic publications.
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| 35. |
- Hansson, Mattias, et al.
(författare)
-
Artifactual insulin release from differentiated embryonic stem cells.
- 2004
-
Ingår i: Diabetes. - 0012-1797. ; 53:10, s. 2603-9
-
Tidskriftsartikel (refereegranskat)abstract
- Several recent reports claim the generation of insulin-producing cells from embryonic stem cells via the differentiation of progenitors that express nestin. Here, we investigate further the properties of these insulin-containing cells. We find that although differentiated cells contain immunoreactive insulin, they do not contain proinsulin-derived C-peptide. Furthermore, we find variable insulin release from these cells upon glucose addition, but C-peptide release is never detected. In addition, many of the insulin-immunoreactive cells are undergoing apoptosis or necrosis. We further show that cells cultured in the presence of a phosphoinositide 3-kinase inhibitor, which previously was reported to facilitate the differentiation of insulin(+) cells, are not C-peptide immunoreactive but take up fluorescein isothiocyanate-labeled insulin from the culture medium. Together, these data suggest that nestin(+) progenitor cells give rise to a population of cells that contain insulin, not as a result of biosynthesis but from the uptake of exogenous insulin. We conclude that C-peptide biosynthesis and secretion should be demonstrated to claim insulin production from embryonic stem cell progeny.
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| 36. |
- Hansson, Magnus L., et al.
(författare)
-
Artificial spider silk supports and guides neurite extension in vitro
- 2021
-
Ingår i: The FASEB Journal. - : John Wiley & Sons. - 0892-6638 .- 1530-6860. ; 35:11
-
Tidskriftsartikel (refereegranskat)abstract
- Surgical intervention with the use of autografts is considered the gold standard to treat peripheral nerve injuries. However, a biomaterial that supports and guides nerve growth would be an attractive alternative to overcome problems with limited availability, morbidity at the site of harvest, and nerve mismatches related to autografts. Native spider silk is a promising material for construction of nerve guidance conduit (NGC), as it enables regeneration of cm-long nerve injuries in sheep, but regulatory requirements for medical devices demand synthetic materials. Here, we use a recombinant spider silk protein (NT2RepCT) and a functionalized variant carrying a peptide derived from vitronectin (VN-NT2RepCT) as substrates for nerve growth support and neurite extension, using a dorsal root ganglion cell line, ND7/23. Two-dimensional coatings were benchmarked against poly-d-lysine and recombinant laminins. Both spider silk coatings performed as the control substrates with regards to proliferation, survival, and neurite growth. Furthermore, NT2RepCT and VN-NT2RepCT spun into continuous fibers in a biomimetic spinning set-up support cell survival, neurite growth, and guidance to an even larger extent than native spider silk. Thus, artificial spider silk is a promising biomaterial for development of NGCs.
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| 37. |
- Hentati-Sundberg, J, et al.
(författare)
-
Fueling of a marine-terrestrial ecosystem by a major seabird colony.
- 2020
-
Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Seabirds redistribute nutrients between different ecosystem compartments and over vast geographical areas. This nutrient transfer may impact both local ecosystems on seabird breeding islands and regional biogeochemical cycling, but these processes are seldom considered in local conservation plans or biogeochemical models. The island of Stora Karlsö in the Baltic Sea hosts the largest concentration of piscivorous seabirds in the region, and also hosts a large colony of insectivorous House martins Delichon urbicum adjacent to the breeding seabirds. We show that a previously reported unusually high insectivore abundance was explained by large amounts of chironomids-highly enriched in δ15N-that feed on seabird residues as larvae along rocky shores to eventually emerge as flying adults. Benthic ammonium and phosphate fluxes were up to 163% and 153% higher close to the colony (1,300m distance) than further away (2,700m) and the estimated nutrient release from the seabirds at were in the same order of magnitude as the loads from the largest waste-water treatment plants in the region. The trophic cascade impacting insectivorous passerines and the substantial redistribution of nutrients suggest that seabird nutrient transfer should be increasingly considered in local conservation plans and regional nutrient cycling models.
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| 38. |
- Hornborg, Sara, et al.
(författare)
-
New policies may call for new approaches: the case of the Swedish Norway Lobster (Nephrops norvegicus) fisheries in the Kattegat and Skagerrak
- 2017
-
Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 74:1, s. 134-145
-
Tidskriftsartikel (refereegranskat)abstract
- The European Common Fisheries Policy has in its 2013 reform increased in complexity, such as a call for coherence with the Marine Strategy Framework Directive and a landing obligation, posing new requirements and challenges to managers, scientists and the fishing industry. Therefore, re-evaluations of current practice are important as a basis for management actions. The Swedish fishery for Norway lobster (Nephrops norvegicus) in the Kattegat–Skagerrak area provides an interesting case study of relevance to emerging policies. Sprung from an unbalance in available fish- and Nephrops quotas and an ambition to protect coastal areas, the current fishery has been directed towards three separate fisheries (mixed trawling, directed trawling using a sorting grid and creeling). Studying direct and indirect effects from alternative Swedish quota allocations among gear types is therefore interesting. Accordingly, a screening study was conducted, taking into consideration area-gear interactions in catch rates, to compare the three different fisheries regarding quantified pressures on the target species, the by-catch species, and on the seafloor, as well as to qualitatively discuss social and economic dimensions. In the next step, alternative quota allocations were studied. In Swedish fisheries, we show that creeling offers a substantial reduction of fishing mortality of both undersized Nephrops and fish and a reduced seafloor pressure per landed kilo of Nephrops. Given that the fishing areas in many cases may be interchangeable between gears, allocating a larger quota share to creels in the Swedish fishery would therefore contribute to the integration of fisheries- and environmental management as called for in the new policies.
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| 39. |
- Howells, Tim, et al.
(författare)
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An evaluation of three measures of intracranial compliance in traumatic brain injury patients
- 2012
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Ingår i: Intensive Care Medicine. - : Springer Science and Business Media LLC. - 0342-4642 .- 1432-1238. ; 38:6, s. 1061-1068
-
Tidskriftsartikel (refereegranskat)abstract
- To compare intracranial pressure (ICP) amplitude, ICP slope, and the correlation of ICP amplitude and ICP mean (RAP index) as measures of compliance in a cohort of traumatic brain injury (TBI) patients. Mean values of the three measures were calculated in the 2-h periods before and after surgery (craniectomies and evacuations), and in the 12-h periods preceding and following thiopental treatment, and during periods of thiopental coma. The changes in the metrics were evaluated using the Wilcoxon test. The correlations of 10-day mean values for the three metrics with age, admission Glasgow Motor Score (GMS), and Extended Glasgow Outcome Score (GOSe) were evaluated. Patients under and over 60 years old were also compared using the Student test. The correlation of ICP amplitude with systemic pulse amplitude was analyzed. ICP amplitude was significantly correlated with GMS, and also with age for patients 35 years old and older. The correlations of ICP slope and the RAP index with GMS and with age were not significant. All three metrics indicated significant improvements in compliance following surgery and during thiopental coma. None of the metrics were significantly correlated with outcome, possibly due to confounding effects of treatment factors. The correlation of systemic pulse amplitude with ICP amplitude was low ( = 0.18), only explaining 3 % of the variance. This study provides further validation for all three of these features of the ICP waveform as measures of compliance. ICP amplitude had the best performance in these tests.
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| 40. |
- Iburg, Sven, et al.
(författare)
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Effects of bottom trawling on the benthic habitat, with special emphasis on bacteria, meio- and macrofaunal diversity and ecosystem functioning
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Commercial bottom trawling can have deleterious effects on benthic communities by causing physical disturbance to sediment structure. Although the impacts of bottom trawling on macrofauna are relatively well studied, less is known about the responses of meiofauna and bacterial communities to such disturbances. Additionally, there is a lack of information on how potential effects of trawling on benthic community structure translate into impacts on ecosystem functions. To address these questions, we conducted a field study in the Baltic Sea (Bornholm area) that sampled 6 sites exposed to different trawling intensities. At each site sediment microbial and meiofauna diversity and community structure was assessed with metabarcoding of the 16S and 18S marker gene, respectively. Macrofauna community structure together with community bioturbation potential and nutrient fluxes were measured to investigate differences in ecosystem functioning in sediments subjected to varying degrees of trawling intensity. While there was a significant effect of bottom trawling intensity on macrofauna community structure, the same was not seen for microbial or meiofauna diversity and community composition Instead, our data showed stronger correlations between microbial and meiofaunal community structure and abiotic factors, in particular sediment pigment content. Similarly, differences in community bioturbation potential and nutrient fluxes were not driven by trawling intensity but were instead linked the abundance of key bioturbators like Scololpos armiger and Limecola balthica at each site. Overall, with the exception of macrofauna community structure, our study did not find significant impacts of bottom trawling on benthic diversity, community composition or function in the commercially fished areas in the Bornholm Basin, Baltic Sea. Our response variables were instead mostly driven by spatial differences in sediment abiotic and biotic parameters between our sampled sites. However, closer examination of a geographically close pair of sites with different trawling intensities showed clear differences in community structure in all three faunal groups. Bottom trawling impacts may therefore be masked by strong spatial variation in abiotic factors, something that should be considered in future studies.
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| 41. |
- Jonsson, Anna, et al.
(författare)
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Cities’ capacity to manage climate vulnerability : experiences from participatory vulnerability assessments in the lower Göta Älv Catchment, Sweden
- 2012
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Ingår i: Local Environment. - : Routledge. - 1354-9839 .- 1469-6711. ; 17:6-7, s. 735-750
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Tidskriftsartikel (refereegranskat)abstract
- Within the scope of this project, tools for conducting systematic and integrated climate vulnerability and sustainability assessments have been developed. Two municipalities in the lower Göta Älv catchment were selected as study cases. Together with representatives from key municipal departments and national government agencies, the interdisciplinary research team designed and conducted a co-production process. Results obtained using the developed tools demonstrate that conducting such a systematic assessment of the current situation and potential impacts of climate change adaptation measures would contribute to synergies between adaptation strategies and other policy arenas. Our recommendation for enhancing the capacity of local vulnerability management in Sweden is to shift foci in four fields: from static analysis of climate vulnerability to a dynamic approach to social vulnerability, from a sectorwise fragmented approach to integrated management, from a focus on technical fixes and physical measures to institutional adaptation measures, and, finally, from sustainability-blind adaptation investments to long-term sustainable climate adaptation measures. The processes and mechanisms for succeeding in this requires that knowledge be produced, shared, and managed in partly new ways, allowing stakeholders both inside and outside local government administration to voice and synergise their concerns and solutions.
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| 42. |
- Jonsson, Krister, et al.
(författare)
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Nerve Tracing in Juvenile Rats : A Feasible Model for the Study of Brachial Plexus Birth Palsy and Cocontractions?
- 2024
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Ingår i: Journal of Brachial Plexus and Peripheral Nerve Injury. - : THIEME MEDICAL PUBL INC. - 1749-7221. ; 19:01, s. e6-e12
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Tidskriftsartikel (refereegranskat)abstract
- Brachial plexus birth injuries cause diminished motor function in the upper extremity. The most common sequel is internal rotation contracture. A number of these patients also suffer from cocontractions, preventing the use of an otherwise good passive range of motion in the shoulder. One theory behind the co-contracture problem is that injured nerve fibers grow into distal support tissue not corresponding to the proximal support tissue, resulting in reinnervation of the wrong muscle groups. To further elucidate this hypothesis, we used rat neonates to investigate a possible model for the study of cocontractions in brachial plexus birth injuries. Five-day-old rats were subjected to a crush injury to the C5-C6 roots. After a healing period of 4 weeks, the infraspinatus muscle was injected with Fluoro-Gold. A week later, the animals were perfused and spinal cords harvested and sectioned. Differences in the uptake of Fluoro-Gold and NeuN positive cells of between sides of the spinal cord were recorded. We found a larger amount of Fluoro-Gold positive cells on the uninjured side, while the injured side had positive cells dispersed over a longer area in the craniocaudal direction. Our findings indicate that the method can be used to trace Fluoro-Gold from muscle through a neuroma. Our results also indicate that a neuroma in continuity somewhat prevents the correct connection from being established between the motor neuron pool in the spinal cord and target muscle and that some neurons succumb to a crushing injury. We also present future research ideas.
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| 43. |
- Jonsson, Patrik, et al.
(författare)
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Different bottom trawl fisheries have a differential impact on the status of the North Sea seafloor habitats
- 2020
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 77, s. 1772-1786
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Tidskriftsartikel (refereegranskat)abstract
- Fisheries using bottom trawls are the most widespread source of anthropogenic physical disturbance to seafloor habitats. To mitigate such disturbances, the development of fisheries-, conservation-, and ecosystem-based management strategies requires the assessment of the impact of bottom trawling on the state of benthic biota. We explore a quantitative and mechanistic framework to assess trawling impact. Pressure and impact indicators that provide a continuous pressure–response curve are estimated at a spatial resolution of 1 × 1 min latitude and longitude (∼2 km2) using three methods: L1 estimates the proportion of the community with a life span exceeding the time interval between trawling events; L2 estimates the decrease in median longevity in response to trawling; and population dynamic (PD) estimates the decrease in biomass in response to trawling and the recovery time. Although impact scores are correlated, PD has the best performance over a broad range of trawling intensities. Using the framework in a trawling impact assessment of ten métiers in the North Sea shows that muddy habitats are impacted the most and coarse habitats are impacted the least. Otter trawling for crustaceans has the highest impact, followed by otter trawling for demersal fish and beam trawling for flatfish and flyshooting. Beam trawling for brown shrimps, otter trawling for industrial fish, and dredging for molluscs have the lowest impact. Trawling is highly aggregated in core fishing grounds where the status of the seafloor is low but the catch per unit of effort (CPUE) per unit of impact is high, in contrast to peripheral grounds, where CPUE per unit of impact is low.
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| 44. |
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| 45. |
- Kristiansson, Helena, et al.
(författare)
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Dura Management Strategies in the Surgical Treatment of Adult Chiari Type I Malformation : A Retrospective, Multicenter, Population-Based Parallel Cohort Case Series
- 2022
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Ingår i: Operative Neurosurgery. - : Lippincott Williams & Wilkins. - 2332-4252 .- 2332-4260. ; 23:4, s. 304-311
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Symptomatic Chiari I malformation is treated with suboccipital decompression and C1 laminectomy. However, whether the dura should be opened (durotomy) or enlarged with a graft (duraplasty) remains unclear. OBJECTIVE: To compare outcomes in adult Chiari I malformation patients treated with duraplasty, durotomy, or without dural opening ("mini-decompression").METHODS: A retrospective, multicenter, population-based cohort study was performed of all adult patients surgically treated for a Chiari I malformation at 3 regional neurosurgical centers between 2005 and 2017. Three different dura management strategies were favored by the participating hospitals, with data stratified accordingly. The primary outcome was measured using the Chicago Chiari Outcome Scale (CCOS), dichotomized into favorable (CCOS >= 13) or unfavorable (CCOS <= 12). Propensity score matching was used to adjust for potential confounders in outcome comparisons.RESULTS: In total, 318 patients were included, of whom 52% were treated with duraplasty, 37% with durotomy, and 11% with mini-decompression. In total, 285 (90%) showed a favorable surgical outcome (CCOS >= 13). Duraplasty was associated with more favorable CCOS and shorter hospital stay compared with durotomy, both in unadjusted (93% vs 84%. P = .018 and 6.0 vs 8.0 days, P < .001) and adjusted analyses (92% vs 84%, P = .044 and 6.0 vs 8.0 days, P < .001). Mini-decompression was excluded from the adjusted analyses because of its small sample size.CONCLUSION: In this study of adult Chiari I malformation, posterior fossa decompression with duraplasty was associated with more favorable postoperative outcome, as determined by the CCOS, compared with posterior fossa decompression with durotomy alone.
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| 46. |
- Lidin, Erik, et al.
(författare)
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Hippocampal Expression of Cytochrome P450 1B1 in Penetrating Traumatic Brain Injury
- 2022
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Ingår i: International Journal of Molecular Sciences. - : MDPI AG. - 1661-6596 .- 1422-0067. ; 23:2
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Tidskriftsartikel (refereegranskat)abstract
- Hippocampal dysfunction contributes to multiple traumatic brain injury sequala. Female rodents’ outcome is superior to male which has been ascribed the neuroprotective sex hormones 17β-estradiol and progesterone. Cytochrome P450 1B1 (CYP1B1) is an oxidative enzyme influencing the neuroinflammatory response by creating inflammatory mediators and metabolizing neuroprotective 17β-estradiol and progesterone. In this study, we aimed to describe hippocampal CYP1B1 mRNA expression, protein presence of CYP1B1 and its key redox partner Cytochrome P450 reductase (CPR) in both sexes, as well as the effect of penetrating traumatic brain injury (pTBI). A total 64 adult Sprague Dawley rats divided by sex received pTBI or sham-surgery and were assigned survival times of 1-, 3-, 5-or 7 days. CYP1B1 mRNA was quantified using in-situ hybridization and immunohistochemistry performed to verify protein colocalization. CYP1B1 mRNA expression was present in all subregions but greatest in CA2 irrespective of sex, survival time or intervention. At 3-, 5-and 7 days post-injury, expression in CA2 was reduced in male rats subjected to pTBI compared to sham-surgery. Females subjected to pTBI instead exhibited increased expression in all CA subregions 3 days post-injury, the only time point expression in CA2 was greater in females than in males. Immunohistochemical analysis confirmed neuronal CYP1B1 protein in all hippocampal subregions, while CPR was limited to CA1 and CA2. CYP1B1 mRNA is constitutively expressed in both sexes. In response to pTBI, females displayed a more urgent but brief regulatory response than males. This indicates there may be sex-dependent differences in CYP1B1 activity, possibly influencing inflammation and neuroprotection in pTBI.
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| 47. |
- Linders, Torsten, 1971, et al.
(författare)
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Distribution and fate of trawling-induced suspension of sediments in a marine protected area
- 2018
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 75:2, s. 785-795
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Tidskriftsartikel (refereegranskat)abstract
- Bottom trawls suspend sediments by physical contact and the drag created by the gear when towed over the seafloor. Increased turbidity and redistribution of sediments may be of concern as some organisms are vulnerable to increased levels of sediment particles in the water column. This study investigates the distribution and fate of trawling-induced suspension of sediments in a coastal marine protected area (MPA). Bottom trawling is allowed in a deep trench of the MPA and regulated to weekdays with weekend closures. We use the closed period as controls to experimentally investigate sediment resuspension generated by the trawling fleet. We find that the turbidity is elevated at trawled depths and originates from small particles of silt–mud seafloor origin that remain suspended for days preventing background levels to be reached during closures. Peaks in the plumes behind trawlers reach levels critical to organisms but decays within hours. Currents in the trench are too weak to resuspend sediments; however, wind-induced resuspension events of elevated turbidity likely originating from nearby shallower areas may occur. Short-term closures and small-scale MPAs are concluded to be of limited use as management tools to reduce effects of resuspension by bottom trawling.
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| 48. |
- Linders, Torsten, 1971, et al.
(författare)
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Particle sources and transport in stratified Nordic coastal seas in the Anthropocene
- 2018
-
Ingår i: Elementa: Science of the Anthropocene. - : University of California Press. - 2325-1026. ; 6:1
-
Forskningsöversikt (refereegranskat)abstract
- Particles of all origins (biogenic, lithogenic, as well as anthropogenic) are fundamental components of the coastal ocean and are re-distributed by a wide variety of transport processes at both horizontal and vertical scales. Suspended particles can act as vehicles, as well as carbon and nutrient sources, for microorganisms and zooplankton before eventually settling onto the seafloor where they also provide food to benthic organisms. Different particle aggregation processes, driven by turbulence and particle stickiness, composition, abundance and size, impact the transport and sinking behavior of particles from the surface to the seafloor. In deep coastal waters, the deposition, resuspension, and accumulation of particles are driven by particle stickiness, composition and aggregate structure. In contrast, wave-driven and bottom current-driven processes in the nepheloid benthic boundary layer of shallow waters are of greater importance to the settling behavior of particles, while the retention capacity of benthic vegetation (e.g., seagrasses) further influences particle behavior. In this review, we consider the various processes by which particles are transported, as well as their sources and characteristics, in stratified coastal waters with a focus on Nordic seas. The role of particles in diminishing the quality of coastal waters is increasing in the Anthropocene, as particle loading by rivers and surface run-off includes not only natural particles, but also urban and agricultural particles with sorbed pollutants and contaminants of organic, inorganic and microplastic composition. Human activities such as trawling and dredging increase turbidity and further impact the transport of particles by resuspending particles and influencing their vertical and horizontal distribution patterns. An interdisciplinary approach combining physical, chemical and biological processes will allow us to better understand particle transport and its impact on coastal waters and estuaries at an ecosystem level. There is a need for development of novel analytical and characterization techniques, as well as new in situ sensors to improve our capacity to follow particle dynamics from nanometer to millimeter size scales.
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| 49. |
- Linders, Torsten, 1971, et al.
(författare)
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Trålskyddsuppföljning i Koster-Väderöfjorden, Sedimentationsundersökning i Spiran
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Inom Kosterhavets nationalpark finns ett antal områden där bland annat trålning inte är tillåtet. Sedan områdena inrättades har det dock inte gjorts någon systematisk utvärdering av deras effektivitet. Länsstyrelsen i Västra Götaland gav i mars 2012 Göteborgs universitet i uppdrag att under 2012 undersöka om trålningen i närheten av trålskyddsområdena ger upphov till uppslamning av sediment som sedan påverkar själva trålskyddsområdena. Under 2012 har vi inom projektet genomfört mätningar i närheten av och inom trålskyddsområdet Spiran under två perioder, dels den 26-27 augusti, dels den 4-19 oktober. Vi mätte från fartyg genom att sänka ner mätinstrument från ytan till nära botten. Detta gav totalt 59 vertikala profiler inne i och runt om trålskyddsområdet. Vi ställde även ut registrerande instrument i trålskyddsområdet under våra två mätperioder. Vi mätte framför allt turbiditet (grumlighet) och ström. Mätningarna var upplagda så att de omfattade både perioder då ingen trålning sker (dvs. helger) och perioder då trålning sker. Vi ser en del tecken på att turbiditeten påverkas av trålningen: • De dagar då det trålas ser vi fler värden med förhöjd turbiditet i de vertikala profilerna. • Djupintervallet med värden med förhöjd turbiditet sammanfaller med intervallet med högre bakgrundsturbiditet. Om de förhöjda turbiditetsvärdena är orsakad av trålning pekar detta på att trålningen även påverkar bakgrundsturbiditeten. • Den kontinuerliga mätningen antyder ett samband med trålningsaktiviteten. När en period av trålning börjar tenderar medelturbiditeten att öka. På motsvarande sätt tenderar medelturbiditeten att minska när trålnigen avslutas. De vertikala profilerna visar att turbiditeten i området runt Spiran präglas av horisontell likformighet, det vill säga att förhållandena inne i trålförbudsområdet liknar förhållandena utanför. Vi ser tecken på att naturliga processer är av stor betydelse. Det gäller framför allt ett mycket tydligt samband mellan turbiditet och tryck i den kontinuerliga mätningen, och att under perioder av vind i kulingstyrka den 9 och särskilt den 17 oktober ökar turbiditeten kraftigt. Hur detta ska tolkas är oklart. Våra mätningar visar dock att bottenströmmarna generellt är för svaga för att kunna erodera sedimenten i området och skapa någon turbiditet.
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| 50. |
- Lindholm, Tomas, et al.
(författare)
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Expression of Semaphorins, Neuropilins, VEGF, and Tenascins in Rat and Human Primary Sensory Neurons after a Dorsal Root Injury
- 2017
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Ingår i: Frontiers in Neurology. - : Frontiers Media SA. - 1664-2295. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Dorsal root injury is a situation not expected to be followed by a strong regenerative growth, or growth of the injured axon into the central nervous system of the spinal cord, if the central axon of the dorsal root is injured but of strong regeneration if subjected to injury to the peripherally projecting axons. The clinical consequence of axonal injury is loss of sensation and may also lead to neuropathic pain. In this study, we have used in situ hybridization to examine the distribution of mRNAs for the neural guidance molecules semaphorin 3A (SEMA3A), semaphorin 3F (SEMA3F), and semaphorin 4F (SEMA4F), their receptors neuropilin 1 (NP1) and neuropilin 2 (NP2) but also for the neuropilin ligand vascular endothelial growth factor (VEGF) and Tenascin J1, an extracellular matrix molecule involved in axonal guidance, in rat dorsal root ganglia (DRG) after a unilateral dorsal rhizotomy (DRT) or sciatic nerve transcetion (SNT). The studied survival times were 1-365 days. The different forms of mRNAs were unevenly distributed between the different size classes of sensory nerve cells. The results show that mRNA for SEMA3A was diminished after trauma to the sensory nerve roots in rats. The SEMA3A receptor NP1, and SEMA3F receptor NP2, was significantly upregulated in the DRG neurons after DRT and SNT. SEMA4F was upregulated after a SNT. The expression of mRNA for VEGF in DRG neurons after DRT showed a significant upregulation that was high even a year after the injuries. These data suggest a role for the semaphorins, neuropilins, VEGF, and J1 in the reactions after dorsal root lesions.
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